ORIGINAL ARTICLE| Volume 55, ISSUE 2, P143-151, April 2020

Effect of 6-week washout period on intraocular pressure following chronic prostaglandin analogue treatment: a randomized controlled trial

Published:November 08, 2019DOI:



      To evaluate the effect of a 6-week washout period on intraocular pressure (IOP) following long-term monotherapy prostaglandin use.


      Prospective, randomized, controlled, single-centre, single-blinded, parallel-group clinical study.


      Subjects aged >18 years diagnosed with open-angle glaucoma or open-angle glaucoma suspects based on elevated IOP in one or both eyes, using monotherapy topical latanoprost, bimatoprost, or travoprost once daily.


      Subjects were prospectively randomized to continue prostaglandin analogue (PGA) monotherapy (control group) or discontinue PGA monotherapy (washout group) for 42 days. IOP was measured at day 0 (day of randomization), 7, 21, and 42.

      Main Outcome Measure

      Mean IOP (mm Hg) ± standard deviation.


      154 eyes (87 participants) completed the study, with 69 eyes (39 participants) in the control group and 85 eyes (48 participants) in the washout group. In the control group, day 0 IOP (14.64 ± 2.68 mm Hg) did not significantly differ from IOP at days 7 (14.25 ± 3.01 mm Hg), 21 (14.57 ± 2.61 mm Hg), and 42 (14.78 ± 2.30 mm Hg) (all p > 0.30). In the washout group, mean IOP values at days 7 (16.19 ± 3.80 mm Hg), 21 (17.28 ± 3.55 mm Hg), and 42 (17.84 ± 3.31 mm Hg) were significantly greater than those at day 0 (14.48 ± 1.94 mm Hg) and day-matched control group values (all p < 0.002). In the washout group, 24.7% of eyes had a day 42 IOP ≥21 mm Hg. No eyes in the control group had a day 42 IOP ≥21 mm Hg.


      Six weeks of PGA washout after long-term monotherapy resulted in a small but statistically significant IOP increase. Majority of washout group participants maintained an IOP lower than 21 mm Hg after the 6-week washout duration. ( identifier, NCT03534882)



      Évaluer l'effet d'un congé thérapeutique de 6 semaines sur la pression intraoculaire (PIO) dans le cadre de l'administration à long terme d'une prostaglandine en monothérapie.


      Étude clinique prospective, comparative, randomisée à simple insu et à groupes parallèles réalisée dans un seul centre.


      Des sujets âgés > 18 ans qui ont fait l'objet d'un diagnostic de glaucome à angle ouvert ou chez lesquels on soupçonnait la présence d'un tel glaucome en raison de la hausse de la PIO dans un œil ou les 2 yeux et qui instillaient un collyre (latanoprost, bimatoprost ou travoprost) en monothérapie une fois par jour.


      Les patients ont fait l'objet d'une randomisation prospective en 2 groupes : poursuite de l'administration de l'analogue de la prostaglandine (APG) à titre de monothérapie (groupe témoin) ou cessation de l'APG en monothérapie (groupe congé thérapeutique) pendant 42 jours. La PIO a été mesurée au jour 0 (jour de la randomisation) de même qu'aux jours 7, 21 et 42.

      Principal paramètre de mesure

      PIO moyenne (mm Hg) ± écart-type.


      Au total, 87 participants (154 yeux) ont poursuivi l’étude jusqu’à la fin : 39 participants (69 yeux) dans le groupe témoin et 48 participants (85 yeux) dans le groupe congé thérapeutique. Au jour 0, la PIO dans le groupe témoin (14,64 ± 2,68 mm Hg) ne différait pas significativement de la PIO mesurée le jour 7 (14,25 ± 3,01 mm Hg), le jour 21 (14,57 ± 2,61 mm Hg) et le jour 42 (14,78 ± 2,30 mm Hg; p > 0,30 pour l'ensemble des mesures). En revanche, la PIO moyenne dans le groupe congé thérapeutique mesurée au jour 7 (16,19 ± 3,80 mm Hg), au jour 21 (17,28 ± 3,55 mm Hg) et au jour 42 (17,84 ± 3,31 mm Hg) était significativement supérieure à la PIO enregistrée au jour 0 (14,48 ± 1,94 mm Hg) et à la PIO mesurée les mêmes jours dans le groupe témoin (p < 0,002 pour l'ensemble des mesures). Dans le groupe congé thérapeutique, la PIO de 24,7 % des yeux se chiffrait à ≥ 21 mm Hg au jour 42. Aucun œil du groupe témoin n'a atteint une PIO ≥ 21 mm Hg au jour 42.


      L'arrêt d'un APG pendant 6 semaines dans le cadre d'une monothérapie de longue durée a entraîné une hausse faible, mais statistiquement significative de la PIO. La majorité des patients du groupe congé thérapeutique ont conservé une PIO inférieure à 21 mm Hg après les 6 semaines de cessation du traitement. (; numéro d’étude : NCT03534882)
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